Chicago police arrested Ahmed Mohamed Mohamed Abou El Ela, 22, at O'Hare International Airport as he was attempting to book a flight to Montana, the FBI said. Immigration agents later took El Ela into custody.

All are being held on administrative immigration violations because they did not report on time to their monthlong program at Montana State University in Bozeman, Mont.

None of the students is considered a terrorism risk and FBI officials stressed that there are no ties between the Egyptians and the alleged terror plot broken up by British authorities.

Three students were arrested Wednesday. The other five Egyptians still are being sought.

Montana State repeatedly tried to contact the missing students. When that failed, the school notified Homeland Security officials and registered the Egyptians as “no-shows” in the system developed after the Sept. 11 attacks to track foreign students.

The government tightened the student visa process after the attacks. One of the hijackers involved in the attacks had arrived in the U.S. with a student visa, and immigration officials approved student visas for two other hijackers after they entered the country. A fourth attended flight training school without a student visa.